Keyhole-plug and guard therefor.



G. S. BATDORF. KEYHOLE PLUG AND GUARD THEREFOR.

' Patented De0.7,1909.

APQLICATION FILED MAY '7, 1909.

invite stars rairnnr t mes.

CHARLES S. BATDORF, OF BROOKLYN, NEW YORK.

KEYI-IOLE-PLUG AND GUARD THEREFOR.

To all whom it may concern:

Be it known that 1, CHARLES S. BATDORF,

a citizen of the United States, residing at Brooklyn, county of Kings,State of New York, have invented certain new and useful Improvements inKeyhole-Plugs and Guards Therefor, of which the following is a full,clear, and exact description.

My invention relates to devices for preventing unauthorized tamperingwith a lock, such, for example, as a lock of a safe deposit box,although it will be evident that the invention may be applied generallyto locks for any purpose.

The invention contemplates broadly the provision of a plug which may beinserted in the keyhole of the lock and a guard which may be so attachedover said plug as to prevent unauthorized removal thereof from thekeyhole. This guard requires broadly a plurality of elementsconstituting the parts of a combination mechanism which when properlyadjusted by a party familiar with the combination may be readily slippedover that portion of the plug which projects outside of the keyhole andby throwing one or more of the combination elements the guard will belocked upon the plug and will at the same time so adjust the plug in thekeyhole as to prevent its withdrawal therefrom.

The mechanism as a whole may be made of compact form, and, if desired,of a size convenient to carry in the pocket of the user.

Vith these and other objects in view, which will appear from thefollowing description, the invention consists in the construction andarrangement of parts, a preferred embodiment of which is illustrated inthe accompanying drawings, in which,

Figure 1 is an edge view of the door of a safe deposit box and locktherefor with my device secured thereto. Fig. 2 is a face view of theparts shown in Fig. 1. Fig. 3 is a part sectional view on the line 3 3Fig. 2 of the door, its lock, and the device secured thereto. Fig. 1 isa rear view of the guard detached. Fig. 5 comprises an elevation and endview of the hub or central post of the guard. Fig. 6 is an enlargeddetail view of one of the combination elements. Fig. '7 is acorresponding view of a cooperating part of one of said elements. Fig. 8is a transverse sectional view of parts shown in Fig. 7 Fig. 9 is anenlarged sectional view of the Specification of Letters Patent.

Application filed May 7, 1909.

Patented ec. 7, 1909.

Serial No. 494,543.

1 parts shown in Fig. 3, Fig. 10 is a view of the keyhole plug withwhich the guard is 1usggl, and Fig. 11 is a sectional view of the 111 Inthe embodiment of the invention herein selected for illustration, 1indicates the door, for example, of a safe deposit box; 2 the lock caseattached to the inside thereof; 3 the locking bolt of said lock.

The particular form of lock with which the device is here illustrated isof the usual cylinder type comprising a cylindrical sleeve 1, withinwhich the lock cylinder 5 is arranged to rotate, said cylinder beingprovided with the usual keyhole slot 6. The cylindrical sleeve 1, ashere shown, is mounted in a suitable aperture 7 in the door 1 andprojects slightly beyond the outer face of the door as indicated inFigs. 1 and 3.

The keyhole plug here selected for illustration consists of the blades 8and 9 ofa thickness adapted to snugly fit the width of the keyhole andare pivoted together at 10. One end of the plate 9 is provided with ashoulder 11 which is adapted when in position in the keyhole to engagethe inner end of the cylindrical sleeve 1, as indicated in Fig. 3, andthe opposite end of said blade is provided with a plurality of lugs 12adapted to be engaged by the combination elements hereinafter to bedescribed. The inner end of the blade 8 has a straight outer edge 13 anda somewhat inclined inner edge 14 to permit the inner ends of the blades8 and 9 when brought together to present together a suiiicientlycontracted width to be easily inserted in the keyhole. The outer end ofthe blade 8 may consistsimply of a straight projection 15, whichcooperates with the lug portion 16 of the blade 9 to hold said lugs inengagement with the combination elements of the guard when the same isslipped over the outer ends of the keyhole plug. Each blade 8 and 9 alsois provided with a lug or shoulder 17, adapted to engage the outer faceof the lock cylinder and thereby determine the extent of insertion ofthe plug within the keyhole.

The combination guard in the form here shown comprises a central hub orpost 18, Fig. 5, which is longitudinally slotted at 19 to receive theouter ends and 16 of the keyhole plug, and is also provided at its outerend with a head or disk 20. The combination elements in the form hereshown consist of a plurality of disks which are rotatably mounted uponthe hub 18, the outer of said disks abutting against the head 20 of thehub 18, as shown in Fig. 3. Each combination element comprises an outerring 21 of suitable material such as steel having preferably brazedtherein an inner case hardened steel ring 22, said inner ring having acounter sunk portion 23 surrounding its central aperture and forming aseat for an apertured disk 24. The inner edge of this disk is providedwith a series of radial notches 25, Fig. 7, all but one of which extendonly partially through the thickness of the disk for the greater portionof their lengths. Also radially arranged in the disk 24 is a notch 26which extends for the greater portion of its length completely throughsaid disk for the purpose hereinafter to be described. The disks 24 areremovably mounted within the rings 22 and are provided withdiametrically opposite pins 27, which, when the disk is in properposition, are arranged to engage suitable apertures 28, Fig. 9,withinthe ring 22. As will be seen from an inspection of Fig. 6, the apertures28 are arranged in diametrically opposite pairs in said ring 22, wherebythe disk 24 may be adjusted to any one of a number of posi- 'tions onsaid ring corresponding to the number of pairs of apertures. The objectof providing for the adjustment of the disks 24 within the rings 22 isto enable the user of the guard to change the combination thereof atwill in the following manner. Each of the outer rings 21 is providedupon its perimeter with a series of numbers 21, Fig. 1, from 0 to 9inclusive, whereby each combination element is capable of providing forten permutations, and the number of permutations provided by the guardas a whole is determined by the number of disks constituting the same.

After the combination elements have been assembled upon the central hub18, they may be secured in place by an outer plate 29, having at itscenter a slot 30 adapted to register with the slot 19 of the hub 18 andhaving also screw holes 31 adapted to register with corresponding holes32 in the end of said hub 18, whereby the plate 29 may be secured tosaid hub with the combination elements or disks confined between it andthe head 20 of the hub. From an inspection of Fig. 3, it will be seenthat the disks 24, when the combination elements are assembled onthe-hub, are spaced apart by reason of the thickness of the rings 22,leaving clearance spaces for the reception of the lugs 12 upon the outerend of the blade 9 of the keyhole plug, when the outer ends of theblades of said plug are expanded within the guard member. To properlyadjust the combination of the guard, each of the disks 24 is provided onits face opposite the notches 25 with an indicating mark 33, shown indotted line Fig. 7, which mark is located at a predetermined positionwith relation to the through slot 26 in said disk, and it is obviousthat it may be in any relative position to said notch. This indicatingmark, when the disk 24 is adjusted on the ring 22, is so arranged as tobe brought opposite any given number on the perimeter of the outer ring21, and will thereby indicate the proper adjustment of the combinationelement as a whole on the central hub 18 to bring the plug receivingslot 26 in alinement with the slot 19 in the central hub 18. In order toindicate to the user the interlocking position of one of thesecombination elements when the guard is assembled, the perimeter of eachof the outside rings is also provided with indicating marks 34 and theinner or securing plate 29 of the guard is provided with a radialprojection 35, also bearing indicating marks 36, with which the marks 34upon the combination elements may be brought into register. Each of theseries of numbers on the perimeter of the outer rings 21 is centrallylocated between successive indicating marks 34, so that when said markson the respective rings 21 are brought into alinement with each otherand with the indicating marks 36 on the projection 35 of the securingblade 29, a series of numbers will be presented transversely of theguard from front to rear, as indicated in Fig. 1, which series ofnumbers constitute the combination necessary to release the guard fromthe keyhole plug. The combination illustrated in Fig. 1 being 1856'0.This combination is secured, for example, by so adjustingthe notcheddisk 24 upon the inner ring 22 of one of the combination elements as tobring the indicating mark 33 on said disk 24 in alinement with thenumeral, for

example, 1, on the innermost combination element of the guard. The markon the adjacent disk has been adjusted to 8, etc., so that when thenumbers 1-8560 on the perimeters of the combination elements are broughtinto alinement, as illustrated in Fig. 1, the notches 26 of each of thedisks 24 will be brought into alinement with the slot 19 of the centralhub 18, whereby the disks may be slipped over or released from the lugs12 of the blade 16 of the keyhole plug.

To hold the combination elements from too free turning on the hub 18 andto facilitate adjustment, spring stop bars 1818, Fig. 11, are arrangedin suitable slots 18 said bars having projections 18 adapted to engageand ride in and out of the notches; 25 in the disks 24, said projections18 being beveled if necessary to facilitate this action.

It will be noted from an inspection of Fig. 3 that the outer projections15 and 16 of the blades of the keyhole plug must be brought together toenable them to enter the passage within the guard formed by the slot 19in the hub and the notches 26 in the successive combination elements,and consequently the inner ends of said blades 8 and 9 will be expandeduntil the shoulder 11 on the blade 9 engages behind the rear end of thesleeve 1 of the cylinder lock or any other convenient partpresented bythe particular construction of lock with which the device is used. Asshown in Fig. 3, the spaces between the lugs 17 engaging the outer faceof the lock and the shoulder 11 on the rear end of the blade 9 are suchas to cause the plug to fit snugly over the ends of the sleeve 4: andthereby prevent undue rattling or movement of the guard or plug on thelock.

In order to prevent an unauthorized manipulator from feeling the lock bycareful and minute rotation of the combination elements to bring theslots 26 into alinement with the lugs 12 of the plug, 1 provide theseries of partial notches 25 corresponding in radial position to thenotch 26, but by reason of the fact that they only extend partiallythrough the disk 24, they will present stop surfaces 37, Fig. 7, toprevent the slipping of the disks 2 1 over the lugs 12 of the plug. Bythis arrangement, it is impossible to properly adjust the combinationelements to secure the necessary combination by the mere feel of thedisks 24 with their notches 25 upon said lugs 12, and this is moreeffectually prevented by the fact that the combination elements are socompactly assembled between the head 20 of the central hub 18 and therear securing plate 29 as to permit of substantially no relativemovement of said elements toward and from each other.

By varying the number of combination elements employed in the guard, thenumber of permutations possible may be varied to any desired extent. Theconstruction here consisting of five elements bearing ten numbers eachpermits of one hundred thousand separate combinations.

In the practical use of the device, the holder of a safe deposit box mayremove the guard and plug from the keyhole and after unfastening thesecuring plate 29 from the rear of the guard may readily remove thecombination disks 24 of one or more of the combination elements andadjust the same to any desired new number, thereby changing thecombination of the guard as a whole. This operation may be effectedwithin a very few moments by reason of the extremely simple structure ofthe guard and the fact that the securing plate 29 may be readily removedsimply by unscrewing the two screws 31 holding the same to the hub 18.By this device therefore the control of the lock is placed wholly withinthe holder of the box and the combination may be altered at convenientintervals to insure the impossibility of any unauthorized person frommanipucombination member having combination elements to engage saidprojecting portion to retain the first member within said key hole.

2. A key hole guard, comprising a member adapted to be inserted withinthe key hole, said member consisting of pivoted elements so arrangedthat upon expansion of the inserted ends of said elements the same willbe retained within the key hole, and a combination member adapted to beslipped upon the projecting ends of said first member, said combinationmember having combination elements arranged to maintain said insertedmembers in expanded position and.

prevent the withdrawal thereof from said key hole.

3. A key hole guard, comprising a member adapted to be inserted withinthe key hole and to be expanded to retain the same therein, and acombination member adapted to be secured upon a projecting portion ofsaid first member and to maintain the same expanded within said keyhole, said combination member consisting of a plurality of combinationelements capable of adjustment to retain the same upon said first memberand to permit the same to be moved from said first member.

4. A key hole guard, comprising a member adapted to be inserted withinthe key hole and retained therein, a combination member adapted toreceive a projecting por tion of said first member and to causeengagement thereof with said key hole, said combination membercomprising a plurality of rotatable disks having portions adapted toengage said first member to prevent separation of said members, saidelements being capable of adjustment to permit removal of saidcombination member from said first member.

5. A keyhole guard comprising a member consisting of two parts pivotedtogether and adapted to be inserted within the keyhole and to beexpanded to retain the same therein, a combination member adapted to beremovably secured on a projecting portion of the first member and tomaintain the same expanded within said keyhole, said combination membercomprising a plurality of combination elements capable of adjustment toretain the same upon said first member and to permit the same to beremoved from said first member.

6. A keyhole guard comprising a member adapted to be inserted in thekeyhole and a combination member adapted to be secured over theprojecting portion of said first member, said combination membercomprising a hub slotted to receive said projecting portion and aplurality of combination elements consisting of disks rotatably mountedon said hub and having slots adapted to be brought into alinement withthe slot in said hub, said combination elements when so alined adaptedto be slipped over said projecting portion of the first member and whenout of alinement adapted to engage said projecting portion and preventseparation of the members, whereby said first member will be securedwithin the keyhole.

7. A keyhole guard comprising a member adapted to be inserted within thekeyhole and to be retained therein, a combination member adapted to besecured upon a projecting portion of said first member, said secondmember comprising a plurality of combination elements arranged to rotatearound said projecting portion of the first member, having means when incertain relative adjustment to maintain the combination member on saidprojecting portion and when in another adjustment to permit sepa rationof said combination member from said first member.

8. A keyhole guard comprising a member adapted to be inserted in thekeyhole and retained therein, a combination member adapted to receive aprojecting portion of said first member, said second member comprising aplurality of combination elements constructed and arranged to be movedrelatively to each other and to said projecting portion, whereby saidcombination element upon proper adjustment of said elements will besecured upon said projecting portion and retain said first member in thekeyhole and upon other relative adjustment will permit free separationof said first and second members and the withdrawal of said first memberfrom said keyhole.

9. A keyhole guard comprising a member adapted to be inserted andretained within the keyhole and having a portion projecting therefrom,and a combination member having means to receive sa d projecting portionand comprising a plurality of disks rotatable about said portion, saiddisks having notches which when alined permit free reception of saidprojecting portion and when out of alinement will engage said projectingportion and prevent separation of said members and withdrawal of saidfirst member from the keyhole.

10. A keyhole guard comprising a member adapted to be inserted andretained in a keyholeand having a portion projecting therefrom, acombination member constructed to receive said projecting portion andcomprising a central slotted hub, a plurality of disks rotatably mountedon said hub, having notches adapted to aline with the slot in said hub,and means on said projecting portion whereby when said slot and notchesare out of alinement, to engage said disks 'to prevent separation ofsaid combination member from said first member and when in alinement topermit free reception of said projecting portion within said combinationmember and free separation of said members.

11. A keyhole guard comprising a member adapted to be inserted andretained within the keyhole and having a portion projecting outside ofthe same, a combination member comprising a central slotted hub andaplurality of combination elements adjustable relatively thereto, saidelements having slots adapted to be brought into and out of alinementwith the slot in said hub, and means on said first member arranged tocooperate with said combination elements, whereby when all of said slotsare brought into alinement, said combination member may be freelyslipped over or removed from said first member, and when the slots of sad members are out of alinement, said combination member will be retainedin engagement with said first member, and serve to retain the samelocked within the keyhole.

12. A keyhole guard comprising a member adapted to be inserted andretained within the keyhole and having a portion projecting outside thesame, a combination member comprising a central slotted hub, a pluralityof combination elements consisting of d sks rotatably mounted on saidhub, each of said disks having a series of radial notches adapted to bealined with a slot in said hub but one of sa d notches of said series ineach disk extending completely through the same, said combinationelements being so arranged that when said through notches are alinedwith the slot in said hub, said combination member may be freely placedover or removed from sa d first member, and when said notches and slotare out of alinement, said members will be secured against separation toretain said first member within the keyhole.

13. A keyhole guard comprising a member adapted to be inserted andretained within the keyhole and having a portion projecting outside thesame, a combination member comprising a central slotted hub, a pluralityof combination elements consisting of disks rotatably mounted on saidhub, each of said disks having a series of radial notches an anted to bealined with a slot in said hub but one of said notches of said series ineach disk extending completely through the same, said combinationelements being so arranged that when said through notches are alinedwith the slot in said hub, said combination member may be freely placedover or removed from said first member, and when said notches and slotare out of alinement, said members will be secured against separation toretain said first member within the keyhole, the remaining notches ofsaid series in each disk serving to prevent feeling of the combination.

14:. A keyhole guard comprising a member adapted to be inserted andretained within the keyhole and having a portion projecting outsidethereof, a combination member comprising a plurality of combinationelements arranged to be rotatably mounted over said projecting portion,said elements having notches adapted to be alined to freely receive saidprojecting portion, having means whereby when said notches are out ofalinement said combination member Will be retained upon said firstmember, said combination elements also having means to prevent feelingof the combination.

15. A keyhole guard comprising a member adapted to be inserted andretained within the keyhole and having a portion projecting outside thesame, a combination member adapted to receive said projecting portionand to be retained thereon to prevent the withdrawal of said firstmentioned member from the keyhole, said combination member comprising aplurality of combination elements, said projecting portion having meansadapted to cooperate with said elements to prevent separation of saidmembers when the latter are in one adjustment and to permit freeseparation thereof when in another adjustment, indicating marks on saidelements to indicate the proper adjustment thereof for separation ofsaid members, and a fixed indicating mark adapted to cooperate with themarks on said elements to determine the proper adjustment of the latter.

16. A keyhole guard comprising a member adapted to be inserted andretained within the keyhole, a combination element constructed andarranged to engage the same within said keyhole, said combination member comprising a central slotted hub, a plurality of combinationelements rotatably mounted thereon, each consisting of an annular ringhaving indicating marks adjacent the perimeter thereof and a centralapertured disk adapted to be removably positioned within said ring, saiddisk having a series of radially arranged notches disposed about itsaperture, one of said notches extending completely through the disk, theremaining notches extending only partially through the disk, saidcombination elements arranged to permit alinement of said radial notcheswith the slot in said hub, whereby when said through notches are alinedWith said slot, the combination member may be readily placed upon orremoved from said first mem ber and when said through notches are out ofalinement, said combination member will be retained upon said firstelement, the remaining notches of the series on each disk being providedto prevent feeling of the combination in conjunction with said firstmember.

M. E. GARRETT.

